Make python script to animate vertex points of any object
import bpy

cell = bpy.data.objects['Cube']
bpy.context.scene.objects.active = cell

basis_key = cell.shape_key_add('basis')
basis_key.keyframe_insert('value', frame=0)

deform_key = cell.shape_key_add()
deform_key.data[0].co = ( 5 , 5 , 5)

deform_key.value = 0.0
deform_key.keyframe_insert('value', frame = 0)

deform_key.value = 1.0
deform_key.keyframe_insert('value', frame = 200)


the main difference in your script is that you set your data_path as "mute" , so just replace data_path="value" then it will work fine